Musical instruments that are constructed from a relatively soft metal such as brass are particularly susceptible to denting when not handled carefully. Brass instruments such as tubas, sousaphones, French horns, and timpani tend to be expensive, complex devices and denting frequently results in damage that diminishes the sound quality, appearance, and value of the instrument.
Currently known dent removal systems which are used for musical instruments such as tubas and sousaphones typically require (i) disassembling the instrument by means of torch-heating soldered joints; (ii) removing the damaged part of the instrument; and (iii) and pounding out the dent by utilizing an appropriate backing surface, usually a shaped piece of steel at the end of a rod, and various types of hammers. Processes of this nature are problematic because they are laborious, time-consuming, and only partially effective. Heating the metal of a musical instrument to the temperature at which solder melts is also likely to damage the lacquered protective finish of the instrument. Furthermore, some musical instruments are plated with silver, and if melted solder runs out of a joint between sections of the instrument, the silver finish will be destroyed if the hot solder comes into contact with the finish.
Another problem associated with commonly used dent removal methods is the damage the hammering process can cause to the metal of the instrument. Repeated hammering of the metal actually thins the metal because as the hammer strikes the surface of the metal, the metal is compressed against the backing surface. The result is significantly weakened metal that is even more susceptible to dents, crack, or punctures. Furthermore, the appearance of a damaged instrument repaired with conventional methods is never truly restored to its pre-damaged state, as some evidence of the repair is always visible on the surface of the instrument.
The tubular portions of some musical instruments are formed from a single sheet of brass that is rolled and notched along the sides of the sheet that contact one another. These notches are then finger-lapped together and brazed to form a tube. Conventional dent repair hammering processes readily damage this type of running joint, making even more extensive repairs a distinct possibility.
Finally, the time required and expense involved with conventional dent repair methods creates additional problems for instrument owners. A tuba with dents covering the bottom branch and the next branch of the instrument can be out of service for months and repairs may cost thousands of dollars per instrument. Thus, a high school band, orchestra, or professional symphony with multiple instruments in need of repair can quickly incur tens of thousands of dollars in expenses each time instrument repairs are undertaken. Therefore, there is a need for a quick, effective, inexpensive, and non-damaging system for removing dents from the metal of musical instruments and from other metals.